[gdal-dev] RFC 35: Delete, reorder and alter field definitions of OGR layers - Call for discussion

[Stephen Woodbridge]

On 5/9/2011 7:54 AM, Martin Dobias wrote:
> Hi Even
>
> On Sat, May 7, 2011 at 7:16 PM, Even Rouault
> <even.rouault at mines-paris.org>  wrote:
>> Hi,
>>
>> I've written a new RFC to add the capability to delete fields, reorder fields
>> and alter field definitions, in OGR layer definitions.
>>
>>         http://trac.osgeo.org/gdal/wiki/rfc35_deletereorderalterfielddefn
>
> Thanks a lot for creating the RFC.
>
> I have just two comments:
> - is the alternation of hte field definition going to have some rules
> how the existing data should be converted to the new type or will the
> driver itself choose how to convert the data? The latter option is
> surely the easier one, but it would be probably good to guarantee at
> least some expected conversions: int<->  text, float<->  text, round
> the number when lowering precision etc.
> - what is actually the motivation behind reordering of the fields? Is
> that just for aesthetical reasons? (e.g. zip code should be next to
> the city name)

Martin,

On rationale, it that some programs, like mapserver, require that all 
files in a tile index have identical attribute column definitions. This 
means same column names, types, widths and column ordering.

In other cases, I do prefer to keep some columns grouped together rather 
than just randomly tacked on to the end so i would use this if it were 
available.

Regards,
   -Steve